<template>
    <div id="app">
        <div class="container">
            <!-- 顶部框模块 -->
            <div class="form-group">
                <div class="input-group">
                    <h4>品牌管理</h4>
                </div>
            </div>

            <!-- 数据表格 -->
            <table class="table table-bordered table-hover mt-2">
                <thead>
                    <tr>
                        <th>编号</th>
                        <th>资产名称</th>
                        <th>价格</th>
                        <th>创建时间</th>
                        <th>操作</th>
                    </tr>
                </thead>
                <tbody>
                    <tr v-for="item in list" :key="item.id">
                        <td>{{ item.id }}</td>
                        <td>{{ item.name }}</td>

                        <!-- 如果价格超过100，就有red这个类 -->
                        <td :class="{ 'red': item.price > 100 }"> {{ item.price }}</td>
                        <td>{{ item.time | dateFormat() }} </td>
                        <td><a href="#" @click="deleteItem(item.id)">删除</a></td>
                    </tr>
                    <tr style="background-color: #EEE">
                        <td>统计:</td>
                        <td colspan="2">总价钱为: {{ allPrice }}</td>
                        <td colspan="2">平均价: {{ svgPrice }}</td>
                    </tr>
                </tbody>

                <tfoot v-if="list.length === 0">
                    <tr>
                        <td colspan="5" style="text-align: center">暂无数据</td>
                    </tr>
                </tfoot>

            </table>

            <!-- 添加资产 -->
            <form class="form-inline">
                <div class="form-group">
                    <div class="input-group">
                        <input type="text" class="form-control" placeholder="资产名称" v-model="name" />
                    </div>
                </div>
                &nbsp;&nbsp;&nbsp;&nbsp;
                <div class="form-group">
                    <div class="input-group">
                        <input type="text" class="form-control" placeholder="价格" v-model="price" />
                    </div>
                </div>

                <br>
                <!-- 阻止表单提交 -->
                <button class="btn btn-primary" @click.prevent="addItem">添加资产</button>
            </form>
        </div>
    </div>
</template>
  
<script>

import moment from 'moment'


export default {


    data() {
        return {
            name: "", // 名称
            price: 0, // 价格
            // list: [
            //     { id: 100, name: "外套", price: 199, time: new Date('2010-08-12') },
            //     { id: 101, name: "裤子", price: 34, time: new Date('2013-09-01') },
            //     { id: 102, name: "鞋", price: 25.4, time: new Date('2018-11-22') },
            //     { id: 103, name: "头发", price: 19900, time: new Date('2020-12-12') }
            // ],
            list: JSON.parse(localStorage.getItem("list")) || [],
        };
    },
    methods: {
        addItem() {
            // 1. 先判断是否为空
            if (this.name.trim() === "" || this.price <= 0) {
                alert("请输入正确的资产信息");
                return;
            }
            this.list.push({
                id: this.list.length + 1,
                name: this.name,
                price: this.price,
                createTime: new Date().toLocaleString()
            });
            this.name = "";
            this.price = 0;
        },
        deleteItem(id) {
            // 1. 先判断是否为空
            if (id <= 0) {
                alert("请输入正确的资产信息");
                return;
            }
            // 2. 找到要删除的元素
            const index = this.list.findIndex(item => item.id === id);
            // 3. 删除
            this.list.splice(index, 1);
        }
    },
    filters: {
        dateFormat(value) {
            return moment(value).format('YYYY-MM-DD');
        }
    },
    computed: {
        allPrice: function () {
            return this.list.reduce((sum, obj) => sum += obj.price, 0)
        },
        svgPrice: function () {
            return (this.allPrice / this.list.length).toFixed(2)
        }
    },
    watch: {
        list: {
            handler(newVal, oldVal) {
                localStorage.setItem('list', JSON.stringify(this.list));
            },
            deep: true,
            immediate: true
        }
    }
};
</script>
  
<style scoped>
.red {
    color: red;
}
</style>